A light-emitting device using a light-emitting diode (LED) is constituted by an LED chip and phosphors.
A white LED light-emitting device that emits white light is constituted by an LED chip that emits light in the blue region and phosphors.
For example, a pseudo-white LED light-emitting device includes a combination of an LED chip that emits blue light and a mixture of phosphors.
For example, a three-wavelength type white LED using an LED chip that emits blue light, and a green light-emitting phosphor, a yellow light-emitting phosphor and a red light-emitting phosphor has been developed.
As one of the red light-emitting phosphors used in light-emitting devices, a K2SiF6:Mn phosphor is known. In order to improve the light-emitting efficiency and the reliability of the light-emitting device, it is necessary to improve the quantum efficiency of the K2SiF6:Mn phosphor.